Adding custom methods to sub-classes in Python – An Example

class Animal(object):

  name = None

  def speak(self):
    print'My name is ', self.name

  def walk(self):
    print "I don’t know how to walk"

  def breath(self):
    print "I don’t know how to breath"

class Dog(Animal):

  breed = None
  
  def speak(self):
    print 'Woof!!'
    
  def whatbreed(self):
    Print "I am a ", self.breed

fido = Dog()
fido.breed = 'pug'
fido.whatbreed()
Output: I am a pug

Note that the whatbreed() class has been added to the subclass Dog() but is not present in the base class Animal().  Only instances of the Dog() class can access this method.